This invention relates generally to the field of footwear, relates specifically to slippers and shoes, and relates in particular to deck shoes. Deck shoes include shoes with a fabric upper, and a rubber outsole, such as tennis shoes, basketball shoes, sneakers and the like.
Conventional footwear includes slippers, which are a low-cut shoe held onto the foot by the upper, which usually consists only of a vamp. They allow a person's foot to be inserted into the throat of the slipper, generally parallel to the sole. A slipper thus engages along the front part of the foot and is not connected to the heel of the foot. The slippers are designed to be put on and taken off easily, but often require a shuffle step to keep them on the foot, and come off easily when running.
Shoes engage not only the toe and instep, but also the heel of a person's foot. Shoes are designed to engage a person's heel so that the back portion of the shoe sole is not free, but moves substantially concurrently with a person's heel. This portion of the shoe is called the heel counter. The shoe is put on by inserting the foot through an expandable throat of the shoe, until the heel counter can be slipped behind the heel of the wearer's foot.
The fit of the shoe can be maintained by laces through eyeholes which allow the throat of the shoe to be expanded so the foot can be inserted into the shoe, whereupon the laces can tighten to adjust the fit of the shoe on the foot. If a slip-on shoe is used, a gore can be used to allow expansion of the throat of the shoe while the foot is inserted, yet maintain the shoe on the foot after the foot is inserted. Whether laces or a gore is used, the heel counter maintains the shoe on the heel of the wearer's foot.
If the heel counter is too stiff or contoured too differently from the heel on the wearer's foot, the wearer's foot will develop blisters. If the heel counter is too flexible, that portion of the shoe will collapse so that the shoe does not maintain adequate contact with the heel of the wearer's foot. This improper contact can lead to blisters, or to a person stepping out of the shoes during walking or running.
Shoes that engage only the front part of a wearer's foot are easy to get on and off, but do not adequately contact and support the heel of the wearer's foot during running or during fast lateral movements. If the wearer begins to lose a shoe during running, it is very easy to actually lose the shoe, fall or twist an ankle. Thus while the slipper type of footwear is easy to put on, it is also easy to take off, intentionally, or inadvertently.
The use of a heel counter on properly fitted shoes can prevent the footwear from coming off inadvertently. However, shoes with a heel counter are time-consuming or awkward to put on and take off. A wearer must bend to tie or untie the laces, or bend to reach the shoe and slip the heel of the foot into the heel counter. Impatient persons, especially children, often try to force the foot into the shoe, collapsing the heel counter.
If the shoe is of cloth construction such as deck shoes, tennis shoes, or sneakers, the heel counter can be stepped on and forced against the insole akin to be used in a manner similar to a slipper. However forcing the heel counter against the insole breaks the heel counter and ruins the shoe. The collapsed heel counter causes the shoe to fit improperly as a slipper and to easily fall off. Further, collapsing the heel counter destroys the strength and rigidity needed to make the shoe fit properly. The importance of maintaining the integrity of the heel counter is shown by the development of the shoehorn, developed to facilitate the insertion of the foot into the shoe without damaging the heel counter.
The time required to put on the shoe or take it off can become unacceptably burdensome in many instances. Japanese customs, for example, often require removing shoes before entering rooms. Workers doing outside work during inclement weather will often remove their shoes before coming inside. If the work activities require constant travel between the inside and outside, the footwear must either be removed and put back on numerous times, or a protective floor covering must be put down.
There is thus a need for a shoe that can be easily put on and taken off when desired, yet not easily fall off the foot when desired. There is a further need for a shoe that can be used as either a slipper engaging the front portion of a foot or, when desired, as a shoe which also engages the heel of the person wearing the shoe.